A precision steel ball reducer

Abstract

A precision steel ball reducer comprises a housing and a fixed plate fixedly connected to the housing, a transmission cavity is formed between the housing and the fixed plate, an input shaft and an output shaft connected to the input shaft are installed in the transmission cavity, a cam is provided on the input shaft between the fixed plate and the output shaft, and a steel ball group consisting of a plurality of steel balls is engaged at the end of the cam; a wavy annular closed groove centered on the axis of the input shaft is provided on the side wall of the fixed plate, an annular elliptical groove concentric with the annular closed groove is provided on the side wall of the output shaft, and the annular closed groove and the annular elliptical groove are used to limit the movement path of the steel ball group; the outer wall of the steel ball group abuts against the shaped closed groove and the annular elliptical groove. The advantages of the present invention are: by directly setting the annular closed groove on the fixed plate and the environmental elliptical groove on the output shaft, the traditional multi-layer planetary disk is simplified, and the transmission efficiency is also guaranteed, the small size can flexibly adapt to various scenes, and the miniaturization effect of the steel ball reducer is achieved.

Description

Technical Field

[0001] The invention relates to a precision steel ball reducer, belonging to the field of reducers. Background Art

[0002] The reducer is an important component in the machinery industry, and its transmission performance directly affects the working performance, production efficiency and product quality of the machinery. Steel ball reducers are widely used in the field of robotics. When their transmission performance meets the requirements, their transmission chain should be as short as possible, so that the mechanism is compact and easy to miniaturize, and can be widely used in the field of robotics. However, the traditional precision cycloid steel ball reducer has a planetary disk as a transmission mechanism, which makes the transmission chain too long and cannot meet the requirements of various environments. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a precision steel ball reducer.

[0004] A precision steel ball reducer comprises a casing and a fixed plate fixedly connected to the casing, a transmission cavity is formed between the casing and the fixed plate, an input shaft and an output shaft connected to the input shaft are installed in the transmission cavity, the input shaft is provided with a cam located between the fixed plate and the output shaft, a steel ball group consisting of a plurality of steel balls is meshed with the end of the cam; a wavy annular closed groove centered on the axis of the input shaft is provided on the side wall of the fixed plate, an annular elliptical groove concentric with the annular closed groove is provided on the side wall of the output shaft, the annular closed groove and the annular elliptical groove are used to limit the movement path of the steel ball group; the outer wall of the steel ball group is in contact with the annular closed groove and the annular elliptical groove, and by directly arranging the annular closed groove on the fixed plate and the environmental elliptical groove on the output shaft, the traditional multi-layer planetary disk is simplified, and the transmission efficiency is also guaranteed, and the small size can flexibly adapt to various scenarios.

[0005] Furthermore, the position states of the steel balls in the steel ball group include steel balls in contact with the outermost side of the annular closed groove and the large diameter of the cam end, steel balls in contact with the innermost side of the annular closed groove and the small diameter of the cam end, and steel balls in contact with the remaining parts of the annular closed groove and the remaining parts of the cam end in sequence. The input shaft drives the cam to rotate so that the steel balls rotate in the annular closed groove, and at the same time are restricted in position by the annular elliptical groove, forming an outer meshing point and an inner meshing point, thereby realizing a fixed-axis output of the rotation speed.

[0006] Furthermore, both sides of the top of the cam are stepped, and an engagement groove for engaging a steel ball group is provided on the top of the cam, so that the cam drives the steel ball group to rotate. The stepped shape makes the reducer compact and easy to miniaturize.

[0007] Preferably, the cam is an elliptical cam, the rotation axis of the elliptical cam is concentric with the axis of the input shaft, and the shape of the elliptical cam limits the radial movement of the steel ball group.

[0008] Furthermore, the number of the annular elliptical grooves is the same as the number of steel balls in the steel ball group, and the transmission action is performed corresponding to the position of each steel ball.

[0009] Furthermore, an input hole is provided on the fixed plate, and one end of the input shaft extends out of the fixed plate through the input hole, and the input shaft is used to connect to an external motor.

[0010] Preferably, the input shaft is provided with a first stop and a second stop in the shape of a step, the first stop and the second stop are respectively located on both sides of the cam, a first bearing is installed on the first stop, and a second bearing is installed on the second stop, which are used to connect with the fixed plate and the output shaft, and the stepped shape of the first stop and the second stop helps the input shaft to be installed in the transmission chamber.

[0011] Preferably, the output shaft is provided with a third stop and a fourth stop in a stepped shape, and a third bearing and a fourth bearing are installed on the third stop and the fourth stop. The output shaft is connected to the casing through the third bearing and the fourth bearing, and can output a stable reduced speed.

[0012] Preferably, a gap adjusting disk is provided on one end face of the casing, and an output hole is provided on the gap adjusting disk. One end of the output shaft extends out of the casing through the output hole and is connected to other transmission components to provide a deceleration effect. The gap adjusting disk adjusts the gap between the steel ball and the meshing pair, so that the deceleration meshing pair is in a gap-free meshing state, thereby improving the transmission accuracy.

[0013] Furthermore, a center hole is provided at the bottom of the output shaft, and the input shaft is connected to the output shaft through the center hole, so the structure is simple and the installation is convenient.

[0014] The beneficial effects of the present invention are as follows: by directly setting the annular closed groove on the fixed plate and the environmental elliptical groove on the output shaft, the traditional multi-layer planetary disk is simplified, and the transmission efficiency is also guaranteed. The small size can flexibly adapt to various scenarios, thereby achieving the miniaturization effect of the steel ball reducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still belong to the scope of the present invention.

[0016] Figure 1 It is a structural diagram of the present invention;

[0017] Figure 2 This is a diagram showing the motion state of the steel ball group relative to the fixed plate in the present invention;

[0018] Figure 3 This is a motion state diagram of the steel ball group relative to the output shaft in the present invention;

[0019] Figure 4 It is the trajectory diagram of the steel ball group relative to the fixed plate;

[0020] Figure 5 It is the motion trajectory diagram of the steel ball group relative to the output shaft;

[0021] Figure 6 It is a simplified diagram of the input shaft structure;

[0022] Figure 7 It is a simplified diagram of the output shaft structure;

[0023] In the figure, 1- housing; 2- fixed plate; 21- annular closed groove; 22- input hole; 3- transmission chamber; 4- input shaft; 41- cam; 42- steel ball; 43- steel ball group; 44- meshing groove; 45- first stop; 46- second stop; 47- first bearing; 48- second bearing; 5- output shaft; 51- annular elliptical groove; 52- third stop; 53- fourth stop; 54- third bearing; 55- fourth bearing; 56- center hole; 6- gap adjustment disk; 61- output hole. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0025] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0026] The directions and positions mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", "inside", "outside", "top", "bottom", "side", etc., are only for reference to the directions or positions of the drawings. Therefore, the directions and positions used are for explaining and understanding the present invention, but not for limiting the scope of protection of the present invention.

[0027] like Figure 1-7As shown, an embodiment of a precision steel ball reducer of the present invention is provided, comprising a housing 1 and a fixed plate 2 fixedly connected to the housing 1, a transmission chamber 3 is formed between the housing 1 and the fixed plate 2, an input shaft 4 and an output shaft 5 connected to the input shaft 4 are installed in the transmission chamber 3, a cam 41 located between the fixed plate 2 and the output shaft 5 is provided on the input shaft 4, a steel ball group 43 composed of a plurality of steel balls is engaged with the end of the cam 41, a wavy annular closed groove 21 centered on the axis of the input shaft 4 is provided on the side wall of the fixed plate 2, an annular elliptical groove 51 concentric with the annular closed groove 21 is provided on the side wall of the output shaft 5, and the annular closed groove 21 and the annular elliptical groove 51 are used to limit the steel ball group The movement path of 43 makes the steel ball 42 move only in the annular closed groove 21 and the annular elliptical groove 51. The outer wall of the steel ball group 43 abuts against the annular closed groove 21 and the annular elliptical groove 51, limiting the axial movement of the steel ball group 43. At the same time, a certain gap is maintained between the cam 41 and the fixed plate 2 and the output shaft 5 to ensure that the cam 41 can rotate normally. The cam 41 limits the radial movement of the steel ball group 43. By directly setting the annular closed groove 21 on the fixed plate 2 and the environmental elliptical groove on the output shaft 5, the traditional multi-layer planetary disk is simplified, and the transmission efficiency is also guaranteed. The small size can flexibly adapt to various scenes, and the miniaturization effect of the steel ball reducer is achieved.

[0028] See also Figure 1-7 The position states of the steel balls 42 in the steel ball group 43 include the steel balls 42 in contact with the outermost side of the annular closed groove 21 and the large diameter of the cam 41 end, the steel balls 42 in contact with the innermost side of the annular closed groove 21 and the small diameter of the cam 41 end, and the steel balls 42 in contact with the remaining parts of the annular closed groove 21 and the remaining parts of the cam 41 end in sequence. The input shaft 4 drives the cam 41 to rotate so that the steel balls 42 rotate in the annular closed groove 21, and are limited in position by the annular elliptical groove 51 to form outer and inner meshing points, thereby realizing the fixed-axis output of the rotation speed. The two sides of the top of the cam 41 are stepped, and an engagement groove 44 for engaging the steel ball group 43 is provided on the top of the cam 41, which is used for the cam 41 to drive the steel ball group 43 to rotate. The stepped shape makes the reducer compact and easier to miniaturize. The cam 41 is an elliptical cam 41 , the rotation axis of the elliptical cam 41 is concentric with the axis of the input shaft 4 , the number of the annular elliptical grooves 51 is the same as the number of the steel balls 42 in the steel ball group 43 , corresponding to the position of each steel ball 42 , a stable transmission action is performed.

[0029] While the steel balls 42 are making relative motion along the elliptical cam end of the input shaft 4, the positions of the steel balls 42 in the steel ball group 43 will move along the annular closed groove 21 of the fixed plate 2 as the input shaft 4 rotates, and the steel ball group 43 forms a certain trajectory relative to the fixed plate 2; while the steel balls 42 in the steel ball group 43 are making relative motion along the elliptical cam 41 end of the input shaft 4, the steel balls 42 move in the annular elliptical groove 51 of the output shaft 5, and the steel balls 42 also form a certain motion trajectory relative to the annular elliptical groove 51, so that the output shaft 5 obtains a lower rotation speed.

[0030] like Figure 1-7 As shown, an embodiment of a precision steel ball reducer of the present invention comprises a housing 1 and a fixed plate 2 fixedly connected to the housing 1, a transmission chamber 3 is formed between the housing 1 and the fixed plate 2, an input shaft 4 and an output shaft 5 connected to the input shaft 4 are installed in the transmission chamber 3, a cam 41 located between the fixed plate 2 and the output shaft 5 is provided on the input shaft 4, a steel ball group 43 composed of a plurality of steel balls 42 is engaged with the end of the cam 41, a wavy annular closed groove 21 centered on the axis of the input shaft 4 is provided on the side wall of the fixed plate 2, an annular elliptical groove 51 concentric with the annular closed groove 21 is provided on the side wall of the output shaft 5, and the annular closed groove 21 and the annular elliptical groove 51 are used to limit the steel ball group The movement path of 43 makes the steel ball 42 move only in the annular closed groove 21 and the annular elliptical groove 51. The outer wall of the steel ball group 43 abuts against the annular closed groove 21 and the annular elliptical groove 51, limiting the axial movement of the steel ball group 43. At the same time, a certain gap is maintained between the cam 41 and the fixed plate 2 and the output shaft 5 to ensure that the cam 41 can rotate normally. The cam 41 limits the radial movement of the steel ball group 43. By directly setting the annular closed groove 21 on the fixed plate 2 and the environmental elliptical groove on the output shaft 5, the traditional multi-layer planetary disk is simplified, and the transmission efficiency is also guaranteed. The small size can flexibly adapt to various scenes, and the miniaturization effect of the steel ball reducer is achieved.

[0031] See also Figure 1-7A center hole 56 is provided at the bottom of the output shaft 5, and the input shaft 4 is connected to the output shaft 5 through the center hole 56. The structure is simple and easy to install. An input hole 22 is provided on the fixed plate 2, and one end of the input shaft 4 extends out of the fixed plate 2 through the input hole 22. The input shaft 4 is used to connect an external motor. A first stop 45 and a second stop 46 in a stepped shape are provided on the input shaft 4. The first stop 45 and the second stop 46 are respectively located on both sides of the cam 41. A first bearing 47 is installed on the first stop 45, and a second bearing 48 is installed on the second stop 46 for connecting with the fixed plate 2 and the output shaft 5. The stepped shape of the first stop 45 and the second stop 46 helps the input shaft 4 to be installed in the transmission chamber 3. A third stop 52 and a fourth stop 53 in a stepped shape are provided on the output shaft 5. A third bearing 54 and a fourth bearing 55 are installed on the third stop 52 and the fourth stop 53. The output shaft 5 is connected to the casing 1 through the third bearing 54 and the fourth bearing 55, and can output a stable deceleration speed.

[0032] See also Figure 1-7 A gap adjusting disk 6 is provided on one end face of the casing 1, and an output hole 61 is provided on the gap adjusting disk 6. One end of the output shaft 5 extends out of the casing 1 through the output hole 61 and is connected to other transmission components to provide a deceleration effect. The gap adjusting disk 6 adjusts the gap between the steel ball 42 and the meshing pair, so that the deceleration meshing pair is in a gap-free meshing state, thereby improving the transmission accuracy.

[0033] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

[0034] Although the invention has been described with reference to several specific embodiments, it should be understood that the invention is not limited to the specific embodiments disclosed. The invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A precision steel ball reducer, characterized in that: The invention comprises a casing and a fixed plate fixedly connected to the casing, a transmission cavity is formed between the casing and the fixed plate, an input shaft and an output shaft connected to the input shaft are installed in the transmission cavity, the input shaft is provided with a cam located between the fixed plate and the output shaft, a steel ball group consisting of a plurality of steel balls is meshed with the end of the cam; a wavy annular closed groove centered on the axis of the input shaft is provided on the side wall of the fixed plate, an annular elliptical groove concentric with the annular closed groove is provided on the side wall of the output shaft, the annular closed groove and the annular elliptical groove are used to limit the movement path of the steel ball group; the outer wall of the steel ball group is in contact with the annular closed groove and the annular elliptical groove.

2. The precision steel ball reducer according to claim 1, characterized in that: The position states of the steel balls in the steel ball group include steel balls contacting the outermost side of the annular closed groove and the large diameter of the cam end, steel balls contacting the innermost side of the annular closed groove and the small diameter of the cam end, and steel balls contacting the rest of the annular closed groove and the rest of the cam end in sequence.

3. The precision steel ball reducer according to claim 2, characterized in that: The two sides of the top of the cam are stepped, and the top of the cam is provided with an engagement groove for engaging the steel ball group, so that the cam drives the steel ball group to rotate.

4. The precision steel ball reducer according to any one of claims 1 to 3, characterized in that: The cam is an elliptical cam, and the rotation axis of the elliptical cam is concentric with the axis of the input shaft.

5. The precision steel ball reducer according to claim 1 or 2, characterized in that: The number of the annular elliptical grooves is the same as the number of the steel balls in the steel ball group.

6. The precision steel ball reducer according to claim 1, characterized in that: An input hole is provided on the fixed plate, and one end of the input shaft extends out of the fixed plate through the input hole.

7. The precision steel ball reducer according to claim 1, characterized in that: The input shaft is provided with a first stop and a second stop in a stepped shape, the first stop and the second stop are respectively located on both sides of the cam, a first bearing is installed on the first stop, and a second bearing is installed on the second stop for connecting with the fixed plate and the output shaft.

8. The precision steel ball reducer according to claim 1, characterized in that: The output shaft is provided with a third stop and a fourth stop in a step shape, and a third bearing and a fourth bearing are installed on the third stop and the fourth stop.

9. The precision steel ball reducer according to claim 1, characterized in that: A gap adjustment disk is provided on one end surface of the housing, an output hole is provided on the gap adjustment disk, and one end of the output shaft extends out of the housing through the output hole.

10. The precision steel ball reducer according to any one of claims 8-9, characterized in that: A center hole is provided at the bottom of the output shaft, and the input shaft is connected to the output shaft through the center hole.

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